Docs / Settings and looks
Settings
Every setting in the Settings window, what it changes, and its default.
On this page
Open Settings with ⌘, or Ctrl+,, or with the Settings button at the bottom of the rail. There is no Save button: each change is kept as you make it.
Theme
Button style
For the bar along the bottom and the Timeline. Icons show their names on hover; words spell them out, and fall back to icons where they would not fit.
When a tab you are closing has changes that are not in the Library. A Starter’s demo, or a snippet just as you saved or opened it, closes without asking.
Find a setting
- Press ⌘F or Ctrl+F in the Settings window, or click the search box at the top of the sidebar.
- Type what you are looking for, such as
memoryorfont size.
A setting matches when every word you type is in its name, its description, its group’s name, or a few other words it is known by. The sidebar keeps only the groups with a match, and each matching setting is framed. When nothing matches, the window says No settings match.
Stops a run that uses more memory than this, before it slows down your computer. Raise it for large data. In the Timeline, the recording may use up to half of it.
JSpark+ lets a Run use from 256 MB to 8 GB. JSpark runs with 1 GB.
The window opens on the group you had open last. In some groups, a small preview at the top shows what the setting under the pointer changes.
General
| Setting | What it does | Default |
|---|---|---|
| Theme | The colours of the app’s own surfaces: Sunny, Calm, Paper, Night, Dusk or Slate. JSpark offers Sunny and Night. | Night |
| Button style | How the buttons along the bottom of the window and the Timeline’s panel toggles read: Icons, Words, or Icons and words. | Icons |
| Ask before closing unsaved work | Asks before you close a tab whose changes are not in the Library. A Starter’s demo closes without asking. | On |
The themes and fonts are on their own page: Themes and fonts.
Editor
| Setting | What it does | Default |
|---|---|---|
| Code colors | How code is coloured in the editor and the console. Six for light Themes, six for dark. JSpark offers Plain and Moss. | Moss (Plain with a light Theme) |
| Font | The face code is drawn in, in the editor and the console. Fira Code and JetBrains Mono come with the app. JSpark offers Fira Code. | Fira Code |
| Text size | How large code is drawn in the editor, from 10 to 24 px. | 13px |
| Wrap long lines | Off: a long line runs on and the editor scrolls sideways. On: it continues on the next row. | Off |
| Suggest while typing | Shows a list of names as you type. | On |
| Show types on hover | Rest the pointer on a name to see its type. Values in the Timeline always show. | On |
| Format before runningJSpark+ | Tidies the code when you press Run or open the Timeline, never while Run as you type runs it. In JSpark it is off; Format Code works in both. | On |
Console
| Setting | What it does | Default |
|---|---|---|
| Text size | How large output is drawn in the console. With Same as the editor on, it follows the editor’s Text size; move the slider to set it apart. | Same as the editor |
| Colored output | Colours values by type: strings, numbers, keys. Off: plain text, as a terminal prints it. | Off |
| Expand objects | Shows objects and arrays opened up when they are printed. Off: one line each, click to open. | Off |
Running
| Setting | What it does | Default |
|---|---|---|
| Run as you type | Runs the code a moment after you stop typing. Off: only when you press Run. Code that reaches outside JSpark waits for Run either way. | On |
| Auto-run delay | How long to wait after your last keystroke before running, from 150 to 1000 ms. | 600ms |
| Time limit | Stops code that stays busy this long without a pause, from 0.1 s to 10 s. In the Timeline, it limits the whole recording. JSpark allows up to 5 s. | 5s |
| Memory limit per run | Stops a Run that uses more memory than this, from 256 MB to 8 GB. In the Timeline, the recording may use up to half. JSpark runs with 1 GB. | 1 GB |
| Don’t run with type errors | Off: type errors are underlined and the code runs anyway. On: they are printed in the console and nothing runs. | Off |
| Language for new Snippets | JavaScript or TypeScript, for each new Snippet. Snippets you already have keep theirs. | JavaScript |
| New Snippets run as | Module (ESM) or Script (CommonJS), for each new Snippet. Snippets you already have keep theirs. | Module (ESM) |
A Node Run also never gets more than half of your computer’s memory. How the two limits work, and what to do when one stops a Run: Time and memory limits.
Timeline
| Setting | What it does | Default |
|---|---|---|
| Step detail | Lines records one Step per line. Inside lines also steps into calls, callbacks and loop checks, and is JSpark+. | Lines |
| Autoplay speed | Steps per second while Autoplay plays, from 0.5x to 100x. 1x is one Step a second. | 2x |
More on the two details: Step Detail.
Starters JSpark+
| Setting | What it does | Default |
|---|---|---|
| Shown StartersJSpark+ | Which Starters the Home screen and the + offer, and in what order. Drag to reorder; switch one off to hide it. With only one on, the + opens it straight away. | All, in the app’s order |
In JSpark, moving or hiding a Starter shows what JSpark+ adds instead.
About
- Version: your edition, the app’s version, and the Node, Chromium and V8 versions your code runs on.
- Copy Diagnostics: copies the versions and your system’s details for a problem report. Never your code, your files or where they are.
- Show Acknowledgements: the open-source software JSpark is built on, with each project’s license.
- Working folder: where Node Snippets run. See The Working Folder.
- Restore defaults…: every setting back to how the app came. See Reset or remove JSpark.
Settings outside this window
A few choices are kept with the rest of your settings but are made where you use them:
- Layout: the Layout menu at the right of the tab strip, or View → Side by Side, Stacked and Swap Panes. See Layout.
- Timeline panels: the switches on the Timeline bar, or View → Timeline Panels.
- The window’s size: JSpark opens at the size you last left it.
The pictures show JSpark on a Mac. On Windows, the window looks a little different and uses Ctrl for ⌘, but everything works the same way.